When working on programs I wrote a year or more ago, I have to re-read the comments and any documentation in order to recollect my thoughts on how it works and

When working on programs I wrote a year or more ago, I have to re-read the comments and any documentation in order to recollect my thoughts on how it works and why I did things the way I did. When working on large programs, I need to keep multiple portions visible in different windows/screens in order to grok the interdependencies. I don't enjoy reading books as much as I used to.